Cut back from 1mg prednisone to 1/2mg and shoulder arm pain returns

Thats a good question. But really depends on a lot of your particulars. Other auto immunes etc. At 1mg your body should be making some cortisol. It probably is not enough for the daily grind of life. If your adrenal system is not damaged from the prednisone use you should be able to tough it out. But thats hard to say without having your cortisol checked. That should be a fairly reliable test at 1mg. The risk is the pain and inflammation restart your PMR. See if tylenol or OTC helps with the pain. You might have to go back to 1mg for a few days then maybe alternate .5 and 1.

My first time with PMR took me 3-1/2 years to taper off with the last 6 months going back and forth between 1mg and 1/2 mg until I could stop taking it with minimal pain (less than 0 to 2 on a scale of 0 to 10). Mostly trying to taper every 2 weeks.

Are you saying that one shoulder only hurts or is it both shoulders? Pain caused by PMR is usually bilateral. If only one side hurts it might not be PMR.

A dilemma with a lot of options. I'm not a doctor but my personal experience would lead me to go back to 1mg for a few days and try a different alternating pattern and take some Tylenol if it helps. Maybe try two days of 1mg, next day .5mg, two days 1mg, next day .5mg.Try that cycle for awhile then alternate daily 1mg and .5mg for awhile before a steady .5mg.
I am now at 4mg. My rheumatologist gave me a tapering schedule to get from 5mg to 1mg. He does not believe in splitting pills. Two weeks of 4mg, two weeks alternating 4mg and 3mg, then two weeks 3mg etc till I get to 1 mg and stay at 1mg til next appt in Feb.
In getting from 5mg to 4mg I did some alternating with 5mg and 4.5mg and managed to get to 4mg in his time frame with no problem. Alternating .5mg tapering doses is what has been working for me. He did not say anything about a plan for getting from 1mg to 0.
I am trying to stay in his time frame.

The 1mg tablet can be cut into 4ths. My feeling is return to 1mg for a week or until comfort resumes, then try reducing to .75mg. (For what it's worth, 1/8th of a 5mg tablet is .625mg. Toward the end, I was taking it as slow as the pill cutter would allow, then skipping the occasional day. Some people find success in alternating days when they taper so they aren't far from their current successful dose until they feel able to move on.

I was down to 1/2 but had to go back to 1mg. Anxiously waiting for lab results screening for myasthenia gravis and cortisol levels now, muscle weakness on exertion and dropping eyelids has my doctor concerned. Not a happy camper with this turn of events.

Your body is telling you the PMR isn't totally gone. Don't give it a chance to come roaring back. I'd go right back to 1 mg. If that doesn't control it, move up the dose a little more. Once you get down to such a minimal dose the potential side effects are virtually zero.

At 3.5, (tapering 0.5 per month) I had several periods of level 3 to 4 pain in one shoulder only. Rather than think about increasing prednisone, and because you are not supposed to mix NSAIDS with prednisone, I asked my doc about trying an Aleve. The answer was that since I was on such a low dose, I could try an Aleve as long as I took a Prilosec as well. I did this twice, separated by a few days. That immediately ended the problem, and I am now at 3 and have not had shoulder (or any) pains since for several weeks.
There can be better ways other than increasing prednisone to deal with non-PMR inflammation. See if your doc will let you try them.

@art43
During a bad flare of my inflammatory arthritis ( I could not walk!) my doctor had me on prednisone and an NSAID called meloxicam. She also had to put me on Carafate to protect my GI tract since I normally cannot take NSAIDS due to negative side effects.
Thank goodness there is way to mix prednisone and NSAIDS together, but only when it is absolutely necessary!!

I have been reducing steadily and comfortably at 0.25mg per week for the last 3 months but when I hit 3mg the PMR started ramping up the next day along with extreme fatigue. Back to 3.25mg and now slowing it down by an extra week or two. Disappointing but can't say I didn't expect difficulty with the last few milligrams. I still have capacity to increase Hydroxychloroquine but waiting on next blood results.